GW4064 inhibits migration and invasion through cathepsin B and MMP2 downregulation in human bladder cancer

The ability of bladder cancer to invade and metastasize often leads to poor prognosis in bladder cancer patients. The aim of this study was to evaluate the effect of the farnesoid X receptor (FXR) agonist GW4064 on the migration and invasion of human bladder cancer cells. Long-term exposure to GW4064 decreased the colony formation of RT4 and T24 cells. The wound healing migration assay revealed an inhibitory effect of GW4064 on both of these bladder cancer cell lines. In addition, integrin β3 expression and myosin light chain phosphorylation were decreased after GW4064 treatment. Immunocytochemistry showed an increase in E-cadherin and a decrease in β-catenin in the cell membrane of bladder cancer cells. Total protein expression and membrane fractionation assays also indicated upregulation of E-cadherin and downregulation of β-catenin. Moreover, GW4064 reduced the invasion of muscle-invasive T24 cells. The GW4064-decreased migration and invasion were reversed by the proteasome inhibitor MG132 and the lysosome inhibitor NH4Cl. Furthermore, the GW4064-induced inhibition of matrix metalloproteinase-2 (MMP2) and cathepsin B expression was reversed by NH4Cl. Xenograft animal studies revealed that GW4064 declined MMP2, cathepsin B and lung metastasis of bladder cancer. In conclusion, GW4064 decreases the migration and invasion of human bladder cancer cells, which may provide a new therapeutic strategy for the treatment of human bladder cancer.